Various push-fit tube couplings are available for connecting tubes together, or for connecting appliances or accessories to tubes. Often these couplings are bulky, due to the need to provide room in the coupling for the assembly of the internal coupling components. Because of this, the coupling itself can be awkward to install due to the space it requires, while the material required for the coupling is greater than would be required if the coupling was of a smaller dimensions.
Applicant has recognised therefore, that a tube coupling of reduced external profile would be desirable, both from a space perspective, and from a material consumption perspective.